               p]
         ]
     (subs (str
-         (if (contains? r :solid)
+         (if (contains-not-null r :solid)
            (str (nextline)
                (generate
                  (merge

    "40" "0.0"
  ]))

(defn common [c]
  (let [parent (:parent c c)]
    (str "8" (nextline) (:layer parent)
        (if (contains? parent :color) (str (nextline) "62" (nextline) (:color parent)) "")
        (if (contains? parent :extrusion) (str (nextline) (point (:extrusion parent) 200)))
        (if (contains? parent :lineType) (str (nextline) "6" (nextline) (:lineType parent)))
        (if (contains? parent :lineWeight) (str (nextline) "370" (nextline) (:lineWeight parent)))
        (if (contains? parent :lineTypeScale) (str (nextline) "48" (nextline) (:lineTypeScale parent)))
        (if (contains? parent :thickness) (str (nextline) "39" (nextline) (:thickness parent)))
    )))

(defmethod generate :face [f]

            ""
        )

        (if (contains-not-null r :line) 
            (join "" (map #(str (nextline) (generate (merge (Line) {:points [(nth points %) (nth points (+ % 1))] :parent r}))) (range 4)))
        )
      ) 1)
